<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    function foo() {
        const test = () => {
            console.log(this)
        }
        test()
    }
    foo()
    let obj = {
        a: 1,
    }
    obj.foo = foo
    obj.foo()
</script>
</body>
</html>
